28 QUESTIONS AND ANSWERS 



Describe the Quevenne lactometer scale. 



The scale is graduated from 15 to 40, each gradu- 

 ation marking one lactometer degree, and figures 

 denote the reading every five degrees. When the 

 floating instrument comes to rest with the surface 

 of the liquid on the 15 mark the liquid has a specific 

 gravity of 1.015, and when it comes to rest in a 

 liquid with the surface on the 40 mark the liquid 

 has a specific gravity of 1.040. Hence to obtain 

 the specific gravity place the figures i.o in front of 

 the lactometer readings. 



At what temperature should the lactometer read- 

 ing be taken? 

 The lactometers are made to be used at 60° F. 



If the milk is at a temperature above or below 

 60° F., can a correction be made on the 

 Quevenne lactometer reading? 



When the temperature of the milk is between 

 60° F. and 70° F., add .1 to the lactometer reading 

 for each degree above 60. When the temperature 

 of the milk is below 60 and above 50 subtract .1 

 from the lactometer reading for each degree below 

 60. This correction is only approximate and can- 

 not be used for wider variations in temperature 

 than those given above. The temperature of milk 

 should be brought within those limits before tak- 

 ing the lactometer reading. 



Describe the New York board of health lactometer. 



It has the general appearance and form of, and 

 is made like, the Quevenne lactometer, but the 

 graduations on the scale are dififerent. 



